Problem #21 : If you have a thick filter (i.e. 5"), the cardboard separators between the filter fins can get displaced making the filter fins collapsed over each other. This can happen with a brand new filter or whenever you pull it in and out. It took me a few days to figure this out after checking most of the potential problems listed in this video. I hope writing this here will help someone and make your day! Great videos by the way, thanks for sharing!!!
One of your best videos yet.I really needed this,you don't know how many jobs I see that have low air loss problems and I see techs just think it's a low refrigerant problem...
Invaluable video OP. You're doing a service for the general public, moreso than just about everyone outside of HVAC school. Thanks again for the video. As a homeowner DIY you're saving countless people the headache of dealing with techs who come out and "top off" the 410. Who don't bother troubleshooting because they just want the quick buck.
@@Dingleberry1856 Fun to read and fun to fill out. I enjoyed doing inspections. Did over 1000 in the short time I was doing it, but fortunately for the realtors, I have stopped doing inspections. I had many happy home buyers while at the same time not too many happy realtors.
Restricted air flow or insufficient air ducts, especially returns, is the VERY common issue with residential A/C systems. For brand new house construction deficient returns can be found on ~95% of the houses! The first house that I had to re-run almost entire air ducts was…. My own house:) It is VERY common issue!
One thing I experienced lately was the blower spinning in the opposite direction creating static pressure and little airflow. Reversing the polarity (swapped positive and negative wire connections at motor) corrected the blower. The blower motor controller module was replaced previously and just happened to cause the motor to spin in the opposite direction, which wasn't noticed until the home owners noticed the AC would not get to the set temp.
Was doing a furnace inspection last Fall and found the High Limit had been bypassed. Thinking the limit may be bad I put a new one in. That didn’t work. It is a 3.5 ton unit. It had 2 x 12” return ducts each 50 feet long , poorly installed and one was completely collapsed. This unit had been operating this way since it was installed. New return duct work was installed solving the problem.
Another airflow problem I have seen many times on mobile homes happens on down flow systems with a clogged or cracked / corroded condensation drain. The overflowing water will pour down into the 12" crossover duct, completely filling it and causing half of the home to have air, but no air to the other half of the home.
Good job I see this crap alot now I found out the hard way bout the secondary heat exchanger clogging plus dont use those 3m filters unless you oversize the filter grill
I had a call back on dirty air filters. the filters were checked during the PM. I checked for a leak and when I was done; I decide to go under the house to check for damage to the ducts. I noticed the EAC and my first thought was to open it. the filters were slammed with dirt. I removed them and told them they had to get a price on a new coil.
Very nice explanation of the cause of low air flow. Most 90* elbows in a duct trunk is equal to 5ft of duct, not all but some are even more equivalent than 5ft. Most common I find is that customers like to move furniture around and cover the grilles, lolol. Maintenance is the Key, clean filter, clean coil. Spot on with all the causes. Very thankful for your professional expertise. HVACR ON AMERICA!!!
Can you make a video on how to figure out whether or not a house has enough supply registers and how to figure out if the return grilles are sized properly, please?
16-year-old 2 ton AC outside unit and coil and gas furnace in the crawl space. Replaced with 3 ton outside unit and coil. Did not change the blower and furnace. I see extensive sweating around the coil, and all the ducts/return etc...; moisture build on the ducts work. Cool is set to high in the blower. Since we have increased the capacity of the AC unit to 3 tons, do I need to replace the blower motor? How do I measure what CFM currently motor is at.
Cannot figure it out, I have a very old noisy unit in what looks like a vented closet. The home is double-wide. The airflow through the vents is very poor and sometimes does not work at all.
What could cause cold air coming from a register during heating system in our first floor bedrooms but our back bedrooms, family room and kitchen receive warm air? We have gas heat, R-19 walls, 9” flexible insulated ducts and dampers above the furnace. Is it possible a duct came loose way up in the attic and the air being pulled by the return is pulling cold attic air into the duct?
Remember an open return or supply in attic or crawl is a 1 2 punch, not only are you losing that CFM to outside, but that same amount of outside air CFM must enter or leave the home to make up pressures.
thanks for the video. Mine issue is a litle bit weird. the Airflow is ok when turn on the heat but only little airfow when use only fan or turn on tha AC. Have some technicians here to check but missed to tell me the cause. It would be very grateful if you could help to analyze.
Awesome videos! Thank you, I found a flex duct in attic that had romex laying over it at the gable end of house, attic vent let sunlight in and broke down the flex so the romex tore through it and caused low flow to room.
So i have a Duct that blows so much air and blows the most air it's a smaller duct, and i have it taped because of that. we just got a HVAC replaced. but it's not distributing enough air to the rest of the house. how can i fix this. thanks in advance. also our ducts are quite old. probably the seals are worn.
Hey Craig as always great video very very important aspect that often times get overlooked. I HAVE 1 REQUESTS CAN U MAKE A VIDEO ON A DAMPER BOARD /ZONING BOARD HOW IT WORKS AND TROUBLESHOOT. WOULD LOVE TO GET A BETTER UNDERSTANDING ON THOSE I HAVE NEVER WORKED ON ONE BUT I KNOW ITS ALOT OUT IN THE FIELD. THANK YOU
I worked 10 yrs for a school district, my 1st air flow issue was on a ancient 10t that had about 4-5" of ice inside and the sieve on a 3" shaft had spun, for whatever reason the key was gone, whomever had repaired it, was too lazy and opted to just drive the set screw into keyway and it destroyed the shaft ($2k,later)
Thank you for detailed to the point info. You mentioned one reason for air movement slow down is the insulation get sucked in and blocks the air. In my case, when I have the ac on for maybe few hours, the air flow slows down on all vents, I listened to the fan blower and I did not hear any different sound than before. So in your advise it seems something is blocking the air flow. But when I turn the a/c off for 10min and back on, the air is normal, and it stays for a a while for another hour or so. My question is, is there something blocking as time passes or is it the coils icing, or can it be the thermostat? It is very coincident when the other day I removed the thermostat case and put it back, because the buttons were not working well on this, ti change time to program it. It's an old one. Any thoughts? Thanks.
NOt a pro. I made the swtich from old mercury thermostats (two floors, one unit) to an Ecobee3. Best move I ever made. Having 2 second floor sensors instead of the main thermostat, and putting the main thermostat (with another sensor) on first floow allows me to see when the unit on/off and the remote temps at the time. This alone is worth its weight in gold.
The proper way to check airflow is with a magnahelic gauge. This should have been done on start up. Most residential equipment is designed to run at no more than .5” total external static pressure. If the pressure is higher, it will affect the CFM capability of the blower. You can take the reading on each side of the system to determine what is restricted, and then work from there.
Hello sir. Quick question about return grill too small or dip switch set wrong. Hime owner says systems had been working fine for years , the it can’t be bad installation right?
I know 1” filters are disliked by many, but retrofitting isn’t in the cards. What 1” filter would you recommend? I like the fiberglass but I’m worried whatever passes through will land inside the system.
I have a Energy Saving Products HV-140 with 42 vent and the unit wired for high speed. The back of the unit is open with a 25" X 16" X 1" filter. The unit doesn't seem to put out the air it should be putting out.
Are ducted systems still popular in America. Because from what I’ve seen when I’ve been on holiday to the U.S most houses seem to use ducted a/c & combustion units. In Britain where I live and most of Europe we tend to use more D.X a/c systems and for heating we have more wet heating systems with radiators etc.
yeah, forced air is still the primary HVAC source in majority of USA, although mini-splits get installed as supplemental source or in smaller new additions
throttle bottle thanks for letting me know. Is there any reason why you use forced air ducted systems? Or is it just more a traditional system you guys tend to go for?
Thank you for all your great vids. I was wondering if you can ever have too much return ducting. After watching your videos, I checked my external static and found 3.5 and 3.5 for a total of 7 in WC . Filter drop is .18 INWC ( 5 inch air bear) and a\c coil drop is .21INWC. ( 2.5 ton N coil.) The temp rise is 70 degrees in heat mode. Rheem says 40-70 rise is okay , so I'm at the high end of acceptable . Shooting for 55 degree rise. I'm thinking I might need more returns and supplies but don't want to over duct it. Any help or advice? Also, when is was installed they added one 10' and one 8 inch flexible return duct. this is a 70,000 BTU Rheem 95% that replaced a 115,000 Ruud 95% furnace. Thank you
That static is way high. 2.5 ton system needs about 1000 cfm airflow, your getting less than 500cfm with the 8” and 10” return flex. Need to add a return or upsize those, you can’t have too much return. Sounds like you are really undersized on the supply side as well.
Will the combination of excess return on the first floor and lack of adequate return on the second floor weaken the second floor supply? In other words, the system overall is getting adequate return, but mostly from first floor. Would this floor-to-floor imbalance result in weak second floor supply? The second floor is hot in Summer by 5 or 6 degrees more than the first floor. I peeked into the first floor return and there's no duct work, just open to the whole wall/framing. Seems like it's pulling air into the return from places it doesn't need to. I was thinking of "ducting" it up with foam board and sealant to force the return to pull more air from the second floor just above that whole opening there. Also going to run jumpers from isolated second floor bedrooms to the main hall/return.
No, the first floors air would be cooler return causing a cooler supply. Sounds like all your cfm is going to the first floor and the second floor is receiving the left overs. Second floors will always be hotter. You may need a dampener system
You would need to go off of a manual J calculation and to be honest, its much easier using a full computer program to determine each rooms btu loss and gain in order to determine the airflow needed in each room, thanks!
I wish I could figure out why my system has low air volume. Its an older goodman ARUf with a time delay relay that has the purple wire in the COM on the relay and the black wire in the COM on the circuit board. I wonder if these need to be switched, as someone had replaced the motor recently. Hmm
just purchased a house, and I turned on the A/C it probably lasted 4 hours to go from 80F to 71F, I put my hands over the vents and you could barley feel the cold air, now I'm watching this thinking damn I'm probably going to have to call an hvac guy.
I have had so many people remove the filter (to improve performance lol) then replace it with a brand new one right before the service call. The coil wont lie, take pictures and watch their faces when presented with the bill for cleaning it. You suddenly know who told them it was a good idea to remove it cause they look at them all mad.
The people that do our yard work (HOA) were taking their blower and blowing into my garage (closed door) and front door. I couldn’t breath and couldn’t understand why. I caught them so I know why now. Called my air conditioner people and the problem is dirty blower wheels. $400.00. Four year old air conditioner on the roof. Apt. Next month to clean it.
just installed a brand new AC system but my daughters room and my room air doesn’t flow with force it’s lagging tech told me something about 3 inch rubber where it should be wider to 7inches or wider don’t know who to trust no more
Hey Craig my Linux thermostat that will not come on And somebody had changed the wires and cut off the old one and added a Black pull out fuse nd the repair man is going take forever I would like to see like a fix myself can You are someone help please I'll Email you a picture
I've got a buddy that's supposed to come over but I figured I would give it a shot on here. My high temperature limit switch keeps killing my furnace. My filter is clean and even when I bypass my high temperature limit switch it's still shuts off and throws the same code. My buddy came over and clean the flame sensor because he thought that it was possible that the fan isn't aware it needs to kick on because the flame sensor was so dirty. Anybody has any more suggestions let me know. I've never cleaned my evaporator coils didn't notice a thing that needed to be done. I've lived in this house for 4 years so I know it's been at least 4 years that they haven't been cleaned. I looked at it from the top and it didn't appear to be crazy dirty. However I couldn't get a good enough angle to see it from the bottom.
#21. loose fan belt on a belt drive blower, #22 adjustable pulley not set properly or worn grooves, # 23 failing fan motor running slow, 3 phase motor running backwards, volume dampers closed too much,
HA HA, that's great! The non important info is what I tend to skip over, sorry! It is Craig Migliaccio and our website is www.acservicetech.com where there are articles, videos, an about section, etc, thanks!
3 ton system (oversized tbh) 9 supply runs of 6 inch pipe, so roughly 900cfm they got 5 runs closed off and even had 3 of them covered with giant magnets to keep their rabbits from getting cold sooo.... 4 6 inch runs to pump some wimpy airflow for 3 tons of air conditioning in humid illinois. Yeah they were pissed when i gave them an earful about their bullshit. They cooked the outdoor unit from years of that bullshit too, i couldnt get the charge dialed in right anymore. Gave up and told them to keep all the registers open from now on and control the temp off the thermostat like a normal human being.
ahh, the game of find the supply registers, only improved upon by the game of "find the return grilles" why doesn't my system heat and cool? you can hear the ducts screaming like a banshee upon entering, well uncover, clean and open all the vents..... I've seen countless of them covered over because "they gather pet hair and dirt", yeah, that's why you have a vacuum cleaner I reply (facepalm)...
Yeah and some techs don't want to ask to go through the building but I find that I need to in order to get the system as a whole approach. I only need to see everything to anticipate what problems we are going to incur next, thanks!
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AC Service Tech LLC will a undersized curb adapter for a RTU cause low airflow if the return and supply portion are too small?
Do you have any recommendations for honest HVAC companies in Las Vegas or how to find one ?
Problem #21 : If you have a thick filter (i.e. 5"), the cardboard separators between the filter fins can get displaced making the filter fins collapsed over each other. This can happen with a brand new filter or whenever you pull it in and out. It took me a few days to figure this out after checking most of the potential problems listed in this video. I hope writing this here will help someone and make your day! Great videos by the way, thanks for sharing!!!
yeah,look closely at those filters don't let the fans suck them in Sometimes they are not glued very well. Elmers glue might work.
One of your best videos yet.I really needed this,you don't know how many jobs I see that have low air loss problems and I see techs just think it's a low refrigerant problem...
David, that is really great to hear, thanks!
Invaluable video OP. You're doing a service for the general public, moreso than just about everyone outside of HVAC school. Thanks again for the video. As a homeowner DIY you're saving countless people the headache of dealing with techs who come out and "top off" the 410. Who don't bother troubleshooting because they just want the quick buck.
Thank You! You are a great teacher who is motivated with great pride for excellence. Keep it up
Thank you very much Matthew!
What a video well explained, I’ll have one of those frozen ones tomorrow, thank you very much
Very, very good video about a problem that service techs will see almost daily in our trade.
Thanks!
Thank you for your support and contribution! I truly appreciate it!!
As a home inspector, I see this stuff all the time, especially shootie workmanship
I think you mean "shoddy" lol
@@jeffreyrogers8151but I like the word "shootie" better. It's cute 😁
I bet your reports are fun to read.
@@Dingleberry1856 Fun to read and fun to fill out. I enjoyed doing inspections. Did over 1000 in the short time I was doing it, but fortunately for the realtors, I have stopped doing inspections. I had many happy home buyers while at the same time not too many happy realtors.
I love your content. Trying to learn as much here. Appreciate every upload every explanation every details
Happy to hear that!
I read the article what im dealing with is Low Vapor Sat Temp, high Superheat, Normal to High Subcooling, but i changed out the txv twice?
Great video! A clogged drain line will also cause a frozen evaporator coil, the water will start to freeze and form ice on the coil.
Yes that happens on freezers but on ac units the saturated temps should not fall below 32 degrees to freeze anything, thanks!
Craig, every video is just amazing, hugs bro
I appreciate that!
Thank you for this small but very informative video. Learned some new things from this video today.
Glad it was helpful!
Restricted air flow or insufficient air ducts, especially returns, is the VERY common issue with residential A/C systems. For brand new house construction deficient returns can be found on ~95% of the houses! The first house that I had to re-run almost entire air ducts was…. My own house:) It is VERY common issue!
Hi there, Craiglemmeachoo. Thanks for the video! Cute cat.
Our pleasure!
Good video. Just received your book. Reading through it now. Great tips.
Awesome thanks Dean Martin!
One thing I experienced lately was the blower spinning in the opposite direction creating static pressure and little airflow. Reversing the polarity (swapped positive and negative wire connections at motor) corrected the blower. The blower motor controller module was replaced previously and just happened to cause the motor to spin in the opposite direction, which wasn't noticed until the home owners noticed the AC would not get to the set temp.
Very good video!
Was doing a furnace inspection last Fall and found the High Limit had been bypassed. Thinking the limit may be bad I put a new one in. That didn’t work. It is a 3.5 ton unit. It had 2 x 12” return ducts each 50 feet long , poorly installed and one was completely collapsed. This unit had been operating this way since it was installed. New return duct work was installed solving the problem.
Any idea on how you would inspect ductwork with no access to attic and most ducting under the floor or behind drywall?
A camera
A pressure test
Thank you!
Great video, things the owner needs to do because the builder cut corners, or hired bad contractors
Helpful information, thank you for sharing !
Thanks so much!
Just ordered the refrigeration book on Amazon yesterday
Awesome, please let me know what you think of it after reading it!
Another airflow problem I have seen many times on mobile homes happens on down flow systems with a clogged or cracked / corroded condensation drain. The overflowing water will pour down into the 12" crossover duct, completely filling it and causing half of the home to have air, but no air to the other half of the home.
Have a Bad Evap Coil furnace Over Heats.Can you Remove the Coil & Run the Furnace Without TiLL the Summer then Replace it?
Craig is the GOAT
Great video that covers a lot in a short amount of time!! Definitely educational and practical.
Thank you very much. Yeah that was many many hours setting up scenes for that 8 minutes, thanks a lot!!!!
Good job I see this crap alot now I found out the hard way bout the secondary heat exchanger clogging plus dont use those 3m filters unless you oversize the filter grill
I had a call back on dirty air filters. the filters were checked during the PM. I checked for a leak and when I was done; I decide to go under the house to check for damage to the ducts. I noticed the EAC and my first thought was to open it. the filters were slammed with dirt. I removed them and told them they had to get a price on a new coil.
Thank you for sharing. I rarely handle the ductwork on install or sales. You got me
Thank you for watching our video!
Very nice explanation of the cause of low air flow. Most 90* elbows in a duct trunk is equal to 5ft of duct, not all but some are even more equivalent than 5ft. Most common I find is that customers like to move furniture around and cover the grilles, lolol. Maintenance is the Key, clean filter, clean coil. Spot on with all the causes. Very thankful for your professional expertise. HVACR ON AMERICA!!!
Thank you very much Ray, yeah couches against return grilles is a big one! thanks!
very informative and TY
Can you make a video on how to figure out whether or not a house has enough supply registers and how to figure out if the return grilles are sized properly, please?
16-year-old 2 ton AC outside unit and coil and gas furnace in the crawl space. Replaced with 3 ton outside unit and coil. Did not change the blower and furnace. I see extensive sweating around the coil, and all the ducts/return etc...; moisture build on the ducts work. Cool is set to high in the blower. Since we have increased the capacity of the AC unit to 3 tons, do I need to replace the blower motor? How do I measure what CFM currently motor is at.
Excellent video. Thanks.
Good video lot's of information. 👍👍
Glad you enjoyed it
Cannot figure it out, I have a very old noisy unit in what looks like a vented closet. The home is double-wide. The airflow through the vents is very poor and sometimes does not work at all.
Thanks alot
My insulated line connected to top of the inside unit has some ice and is wet . Not kicking in full power just partly running
The cat was very appreciative that you moved to the furniture just for it to lay across the supply register...
What could cause cold air coming from a register during heating system in our first floor bedrooms but our back bedrooms, family room and kitchen receive warm air? We have gas heat, R-19 walls, 9” flexible insulated ducts and dampers above the furnace. Is it possible a duct came loose way up in the attic and the air being pulled by the return is pulling cold attic air into the duct?
Remember an open return or supply in attic or crawl is a 1 2 punch, not only are you losing that CFM to outside, but that same amount of outside air CFM must enter or leave the home to make up pressures.
thanks for the video. Mine issue is a litle bit weird. the Airflow is ok when turn on the heat but only little airfow when use only fan or turn on tha AC. Have some technicians here to check but missed to tell me the cause. It would be very grateful if you could help to analyze.
I have this exact same problem, the a/c blows cold, but low air flow. Wondering what some troubleshooting ideas could be? 🤔
Awesome videos! Thank you, I found a flex duct in attic that had romex laying over it at the gable end of house, attic vent let sunlight in and broke down the flex so the romex tore through it and caused low flow to room.
How would I know if the trunk is not sized correctly?
2:37 for the win!
My son's cat is his identical twin. LOL
Very informative video. Thanks again.
So i have a Duct that blows so much air and blows the most air it's a smaller duct, and i have it taped because of that. we just got a HVAC replaced. but it's not distributing enough air to the rest of the house. how can i fix this. thanks in advance. also our ducts are quite old. probably the seals are worn.
Hey Craig as always great video very very important aspect that often times get overlooked. I HAVE 1 REQUESTS CAN U MAKE A VIDEO ON A DAMPER BOARD /ZONING BOARD HOW IT WORKS AND TROUBLESHOOT. WOULD LOVE TO GET A BETTER UNDERSTANDING ON THOSE I HAVE NEVER WORKED ON ONE BUT I KNOW ITS ALOT OUT IN THE FIELD. THANK YOU
Sd sd thanks for letting me know what you would like to see!
Great video and info!! Sir where are you located?
Great job and video
Thanks for the visit
I worked 10 yrs for a school district, my 1st air flow issue was on a ancient 10t that had about 4-5" of ice
inside and the sieve on a 3" shaft had spun, for whatever reason the key was gone, whomever had repaired
it, was too lazy and opted to just drive the set screw into keyway and it destroyed the shaft ($2k,later)
Great Video. Thank you for sharing . How do I check and diagnose bad Metering Device and fix , replaced it ? Thank you.
ZE Kenzy. Check out the articles I have on the website for frozen evap coil and liquid line restriction, thanks!
Thank you for detailed to the point info. You mentioned one reason for air movement slow down is the insulation get sucked in and blocks the air. In my case, when I have the ac on for maybe few hours, the air flow slows down on all vents, I listened to the fan blower and I did not hear any different sound than before. So in your advise it seems something is blocking the air flow. But when I turn the a/c off for 10min and back on, the air is normal, and it stays for a a while for another hour or so. My question is, is there something blocking as time passes or is it the coils icing, or can it be the thermostat? It is very coincident when the other day I removed the thermostat case and put it back, because the buttons were not working well on this, ti change time to program it. It's an old one. Any thoughts? Thanks.
NOt a pro. I made the swtich from old mercury thermostats (two floors, one unit) to an Ecobee3. Best move I ever made. Having 2 second floor sensors instead of the main thermostat, and putting the main thermostat (with another sensor) on first floow allows me to see when the unit on/off and the remote temps at the time. This alone is worth its weight in gold.
I have a High Efficiency unit. The heat exchanger would have to be removed to clean the underside of a “A” coil I’m guessing???
What if you have supply ducts connected to the top of the plenum
Very helpful!
WHat about problem #21 being that the condenser coils on the AC are dirty and blocked with debris and dirt?
The proper way to check airflow is with a magnahelic gauge. This should have been done on start up. Most residential equipment is designed to run at no more than .5” total external static pressure. If the pressure is higher, it will affect the CFM capability of the blower. You can take the reading on each side of the system to determine what is restricted, and then work from there.
Hello sir. Quick question about return grill too small or dip switch set wrong. Hime owner says systems had been working fine for years , the it can’t be bad installation right?
Just because it works doesn't mean it is working well!
Very nicely explained,god bless you.
Thanks a lot! Appreciate the support!
I know 1” filters are disliked by many, but retrofitting isn’t in the cards. What 1” filter would you recommend? I like the fiberglass but I’m worried whatever passes through will land inside the system.
I have a defunct electrostatic filter on a Carrier so now i use 18x21x1 inch pleated filters I get in a 2pk from Walmart, not a perfect fit but works.
I have a Energy Saving Products HV-140 with 42 vent and the unit wired for high speed. The back of the unit is open with a 25" X 16" X 1" filter. The unit doesn't seem to put out the air it should be putting out.
excellent explaining as usual craig. two thumsbs up
Thanks a lot Mohamed!
Good vid Craig ...
Thank you!
I wish there is also one for noisy HVAC.
I just cleaned the fan. 1/4in of dust on each one. It looked like a bunch of rectangles, didn't recognize there were blades there.
Are ducted systems still popular in America. Because from what I’ve seen when I’ve been on holiday to the U.S most houses seem to use ducted a/c & combustion units. In Britain where I live and most of Europe we tend to use more D.X a/c systems and for heating we have more wet heating systems with radiators etc.
yeah, forced air is still the primary HVAC source in majority of USA, although mini-splits get installed as supplemental source or in smaller new additions
throttle bottle thanks for letting me know. Is there any reason why you use forced air ducted systems? Or is it just more a traditional system you guys tend to go for?
Thank you for all your great vids.
I was wondering if you can ever have too much return ducting.
After watching your videos, I checked my external static and found 3.5 and 3.5 for a total of 7 in WC .
Filter drop is .18 INWC ( 5 inch air bear) and a\c coil drop is .21INWC. ( 2.5 ton N coil.)
The temp rise is 70 degrees in heat mode. Rheem says 40-70 rise is okay , so I'm at the high end of acceptable . Shooting for 55 degree rise.
I'm thinking I might need more returns and supplies but don't want to over duct it. Any help or advice? Also, when is was installed they added one 10' and one 8 inch flexible return duct.
this is a 70,000 BTU Rheem 95% that replaced a 115,000 Ruud 95% furnace. Thank you
That static is way high. 2.5 ton system needs about 1000 cfm airflow, your getting less than 500cfm with the 8” and 10” return flex. Need to add a return or upsize those, you can’t have too much return. Sounds like you are really undersized on the supply side as well.
thanks, partner for sharing!!!!.
Thanks Jimbola77!
Thanks for driving during this time when everyone needs supplies too!
Will the combination of excess return on the first floor and lack of adequate return on the second floor weaken the second floor supply? In other words, the system overall is getting adequate return, but mostly from first floor. Would this floor-to-floor imbalance result in weak second floor supply? The second floor is hot in Summer by 5 or 6 degrees more than the first floor. I peeked into the first floor return and there's no duct work, just open to the whole wall/framing. Seems like it's pulling air into the return from places it doesn't need to. I was thinking of "ducting" it up with foam board and sealant to force the return to pull more air from the second floor just above that whole opening there. Also going to run jumpers from isolated second floor bedrooms to the main hall/return.
No, the first floors air would be cooler return causing a cooler supply. Sounds like all your cfm is going to the first floor and the second floor is receiving the left overs. Second floors will always be hotter. You may need a dampener system
Mine blows but really weak and we changed evrey filter and it gets hot because no cold air any help
How do you measure or calculate each room in terms of capacity?
You would need to go off of a manual J calculation and to be honest, its much easier using a full computer program to determine each rooms btu loss and gain in order to determine the airflow needed in each room, thanks!
AC Service Tech LLC can you do a video on that? Thanks
I wish I could figure out why my system has low air volume. Its an older goodman ARUf with a time delay relay that has the purple wire in the COM on the relay and the black wire in the COM on the circuit board. I wonder if these need to be switched, as someone had replaced the motor recently. Hmm
just purchased a house, and I turned on the A/C it probably lasted 4 hours to go from 80F to 71F, I put my hands over the vents and you could barley feel the cold air, now I'm watching this thinking damn I'm probably going to have to call an hvac guy.
Great info
Nice sir👍
Thanks
Most welcome
2:30 cozy cat, excellent.
I love your videos maker more👍👍😄😄
Thanks a lot Reid!
Very useful video
Glad you think so!
I have had so many people remove the filter (to improve performance lol) then replace it with a brand new one right before the service call. The coil wont lie, take pictures and watch their faces when presented with the bill for cleaning it. You suddenly know who told them it was a good idea to remove it cause they look at them all mad.
The people that do our yard work (HOA) were taking their blower and blowing into my garage (closed door) and front door. I couldn’t breath and couldn’t understand why. I caught them so I know why now. Called my air conditioner people and the problem is dirty blower wheels. $400.00. Four year old air conditioner on the roof. Apt. Next month to clean it.
I lived in this house for 9 years before someone found that the furnace fan was set at low speed. Ugh. So cold in the winter.
Great. Thanks for the vid bud!
You bet!
have a mobile home with the duct work inside blankey on both sides of home no way to inspect without destroying insulation blanket
just installed a brand new AC system but my daughters room and my room air doesn’t flow with force it’s lagging tech told me something about 3 inch rubber where it should be wider to 7inches or wider don’t know who to trust no more
Ty nice video
Glad to help Jonathan!
Thanks
Is it possible for a duck to make a nest in a duct
That has to with migration patterns and the location of the building along with the visibility of the air conditioner from the sky!
The duck may need to duck if the duct is undersized.
I think the kitty-cat stole the show at 2:35...
Hey Craig my Linux thermostat that will not come on And somebody had changed the wires and cut off the old one and added a Black pull out fuse nd the repair man is going take forever I would like to see like a fix myself can You are someone help please I'll Email you a picture
I've got a buddy that's supposed to come over but I figured I would give it a shot on here. My high temperature limit switch keeps killing my furnace. My filter is clean and even when I bypass my high temperature limit switch it's still shuts off and throws the same code. My buddy came over and clean the flame sensor because he thought that it was possible that the fan isn't aware it needs to kick on because the flame sensor was so dirty. Anybody has any more suggestions let me know. I've never cleaned my evaporator coils didn't notice a thing that needed to be done. I've lived in this house for 4 years so I know it's been at least 4 years that they haven't been cleaned. I looked at it from the top and it didn't appear to be crazy dirty. However I couldn't get a good enough angle to see it from the bottom.
#21. loose fan belt on a belt drive blower, #22 adjustable pulley not set properly or worn grooves, # 23 failing fan motor running slow, 3 phase motor running backwards, volume dampers closed too much,
19 problems a technician can fix and one problem that is intermittent and hard to price the repair of @2:31! 🤣
Yeah its a problem when a huge dog lays on a heavy gauge floor grille!
What is this guys name it sounds like he says crummy gleotchu I am not trying to make fun but I just can not make it out.
HA HA, that's great! The non important info is what I tend to skip over, sorry! It is Craig Migliaccio and our website is www.acservicetech.com where there are articles, videos, an about section, etc, thanks!
3 ton system (oversized tbh)
9 supply runs of 6 inch pipe, so roughly 900cfm
they got 5 runs closed off and even had 3 of them covered with giant magnets to keep their rabbits from getting cold
sooo.... 4 6 inch runs to pump some wimpy airflow for 3 tons of air conditioning in humid illinois. Yeah they were pissed when i gave them an earful about their bullshit. They cooked the outdoor unit from years of that bullshit too, i couldnt get the charge dialed in right anymore. Gave up and told them to keep all the registers open from now on and control the temp off the thermostat like a normal human being.
ahh, the game of find the supply registers, only improved upon by the game of "find the return grilles"
why doesn't my system heat and cool? you can hear the ducts screaming like a banshee upon entering, well uncover, clean and open all the vents..... I've seen countless of them covered over because "they gather pet hair and dirt", yeah, that's why you have a vacuum cleaner I reply (facepalm)...
Yeah and some techs don't want to ask to go through the building but I find that I need to in order to get the system as a whole approach. I only need to see everything to anticipate what problems we are going to incur next, thanks!
i think ductless split unit is the future....
I think you are right!
2:36 what air supply are you talking about? 🤣